

#import <Foundation/Foundation.h>
#import <UIKit/UIKit.h>
@interface NSString (Category)
- (CGSize)sizeWithFont:(UIFont *)font maxSize:(CGSize)maxSize;
- (BOOL)isPureInt;
/**
 *@description 判断字符串是否存在
 *  yes 不存在或者为""  no 存在
 */
- (BOOL)ap_isNullString;
- (NSString *)urlEncode;
- (NSString *)md5String;
@end
